Doug Peterson writes about Expresso, an interesting writing analytics project created by Mikhail Panko, a PhD student in computational neuroscience (you can see the open source for yourself on GitHub.) Give it a few paragraphs of your own writing and it will analyize it for weak verbs, filler words, negations, modals, passive voice, and more. Not all of these are bad (I was pleased to have a substantially high rare word count) but many of them are (and hence I had 5 percent weak verbs and 0.1 percent passive voice).